1. Field of the Invention
The present invention relates to an endoscope including an operation portion through which internal components of the endoscope such as bending wires, fluid tubes, and a signal cable are inserted.
2. Description of the Related Art
Endoscopes are used in the medical field, the industrial field and other fields. Endoscopes include a so-called electronic endoscope incorporating an image pickup apparatus at a distal end portion of an insertion portion. The medical electronic endoscope (hereinafter “endoscope”) 1 shown in FIG. 1 generally includes an operation portion 3 on a proximal end side of an insertion portion 2 which has flexibility.
The operation portion 3 is configured by integrally fixing an operation portion main body 3A and a grasping portion case body 3B. The operation portion main body 3A is provided with a bending operation apparatus 4, an air/water feeding button 5, and a suction button 6.
A reference sign 7 represents a universal cable, and the universal cable extends from the operation portion main body 3A.
The bending operation apparatus 4 includes an up/down knob 4UD and a left/right knob 4LR. A bending portion of the insertion portion 2 (not shown) bends in an upper direction or a lower direction in accordance with an operation of the up/down knob 4UD. Also, the bending portion bends in a left direction or a right direction according to an operation of the left/right knob 4LR.
Note that a reference sign 8 represents a treatment instrument insertion port, and the treatment instrument insertion port is provided at a grasping portion case body 3B. The treatment instrument insertion port has an opening through which an endoscope treatment instrument such as forceps, not shown, is inserted and removed.
The endoscope 1 including the bending operation apparatus 4, the air/water feeding button 5 and the suction button 6 includes as the endoscope internal components, the bending wires which extend from the bending portion, and fluid tubes, light guide fiber bundles, a signal cable, and the like, which extend from the distal end portion of the insertion portion (not shown).
As shown in FIG. 2 and FIG. 3, the endoscope internal components inserted through the insertion portion 2 are passed through the insertion portion 2, and guided into an operation portion internal space 10 that is an internal space of the operation portion 3.
As shown in FIG. 2, the operation portion internal space 10 is divided into two spaces: a first space 11 and a second space 12. A reference sign 13 represents a main board, and the main board divides the operation portion internal space 10. The main board 13 is disposed in parallel with a direction of the longitudinal axis of the operation portion 3.
The bending wires are guided into the first space 11. The bending wires are four bending wires 14U, 14D, 14L and 14R corresponding to four bending directions of the bending portion, i.e., upper, lower, left and right directions.
The fluid tubes, the light guide fiber bundles and the signal cable are guided into the second space 12. The fluid tubes are, for example, an air feeding tube 15a and a water feeding tube 15w1 which correspond to the air/water feeding button 5, and a suction tube 15s and an auxiliary water feeding tube 15w2 which correspond to the suction button 6. For example, the two light guide fiber bundles which are the fiber bundles 16a, 16b (hereinafter “fiber bundles”) are provided so as to correspond to the number of illumination windows. The signal cable 17 is extended from the image pickup apparatus (not shown), and configured by a plurality of signal wires combined into one bundle.
As shown in FIG. 3, the air feeding tube 15a, the water feeding tubes 15w1 and 15w2, the suction tube 15s that also serves as a treatment instrument channel tube, the two fiber bundles 16a, 16b, and the signal cable 17 are disposed in the second space 12 constituting one surface side of the main board 13 in the operation portion internal space 10.
One end of the air feeding tube 15a guided into the second space 12 is coupled to one end of a first tube 19a whose other end is coupled to the air/water feeding button 5 via an air feeding tube coupler 18a. One end of the water feeding tube 15w1 guided into the second space 12 is coupled to one end of a second tube 19w1 whose other end is coupled to the air/water feeding button 5 via a first water feeding tube coupler 18w1. One end of the auxiliary water feeding tube 15w2 guided into the second space 12 is coupled to one end of a third tube 19w2 which extends to an endoscope coupler, not shown, via the second water feeding tube coupler 18w2. One end of the suction tube 15s guided into the second space 12 is coupled to one end of a fourth tube 19s whose other end is coupled to the suction button 6 by the suction tube coupler 18s. 
The various tubes 15a, 15w1, 15w2, 15s, 19a, 19w1, 19w2 and 19s, the light guide fiber bundles 16a, 16b, and the signal cable 17 each has a predetermined elasticity (or hardness). The various tubes 15a, 15w1, 15w2, 15s, 19a, 19w1, 19w2 and 19s, the light guide fiber bundles 16a, 16b, and the signal cable 17 are disposed to be in a predetermined slack state in the operation portion 3 so as to each reciprocate with respect to a longitudinal direction of the operation portion in the operation portion internal space 10.
Accordingly, the various tube 15a, 15w1, 15w2, 15s, 19a, 19w1, 19w2 and 19s, the light guide fiber bundles 16a, 16b, and the signal cable 17 can be prevented from becoming tight due to a bending action of the bending portion.
Note that the upward bending wire 14U, the downward bending wire 14D, the leftward bending wire 14L, and the rightward bending wire 14R guided into the first space 11 are disposed on the other surface side of the main board 13.
After disposing the aforementioned various endoscope internal components, an operator moves the grasping portion case body 3B from the side of the insertion portion 2 to the side of the operation portion main body 3A as shown in an arrow Y4, and integrally combines the operation portion main body 3A and the case body 3B, as shown in FIG. 4.
Japanese Patent Application Laid-Open Publication No. H8-36137 discloses an assembly portion inside the endoscope, which is designed so as to even assembly states of various members, eliminate variation in durability or damages of optical fiber bundles and make the assembling work to be finished in a short time. The assembly portion in the endoscope includes a main board showing an actual layout drawing of various members including optical fiber bundles such as a light guide and an image guide, an air feeding pipe, and a water feeding pipe, which are arranged inside the endoscope operation portion. Assembly sequence numbers are added to marks of the respective members in the layout drawing, and the same numbers are added to the various members to be assembled. As a result, arranging the various members according to the layout drawing and the sequence numbers enables different operators to assemble the various members in the same manner.
An experienced skill is required for a technique of assembling a plurality of endoscope internal components in a short time while keeping a degree of freedom for reciprocation in a longitudinal direction of the operation portion in the internal space of the operation portion.